/*
 * Copyright (C) 2008 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect.testing;

import com.google.common.annotations.GwtCompatible;

import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.Map.Entry;

/**
 * A container class for the five sample elements we need for testing.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
public class SampleElements<E> implements Iterable<E>
{
    // TODO: rename e3, e4 => missing1, missing2
    private final E e0;
    private final E e1;
    private final E e2;
    private final E e3;
    private final E e4;

    public SampleElements(E e0, E e1, E e2, E e3, E e4)
    {
        this.e0 = e0;
        this.e1 = e1;
        this.e2 = e2;
        this.e3 = e3;
        this.e4 = e4;
    }

    @Override
    public Iterator<E> iterator()
    {
        return asList().iterator();
    }

    public List<E> asList()
    {
        return Arrays.asList(e0(), e1(), e2(), e3(), e4());
    }

    public static class Strings extends SampleElements<String>
    {
        public Strings()
        {
            // elements aren't sorted, to better test SortedSet iteration ordering
            super("b", "a", "c", "d", "e");
        }

        // for testing SortedSet and SortedMap methods
        public static final String BEFORE_FIRST = "\0";
        public static final String BEFORE_FIRST_2 = "\0\0";
        public static final String MIN_ELEMENT = "a";
        public static final String AFTER_LAST = "z";
        public static final String AFTER_LAST_2 = "zz";
    }

    public static class Chars extends SampleElements<Character>
    {
        public Chars()
        {
            // elements aren't sorted, to better test SortedSet iteration ordering
            super('b', 'a', 'c', 'd', 'e');
        }
    }

    public static class Enums extends SampleElements<AnEnum>
    {
        public Enums()
        {
            // elements aren't sorted, to better test SortedSet iteration ordering
            super(AnEnum.B, AnEnum.A, AnEnum.C, AnEnum.D, AnEnum.E);
        }
    }

    public static class Ints extends SampleElements<Integer>
    {
        public Ints()
        {
            // elements aren't sorted, to better test SortedSet iteration ordering
            super(1, 0, 2, 3, 4);
        }
    }

    public static <K, V> SampleElements<Entry<K, V>> mapEntries(
            SampleElements<K> keys, SampleElements<V> values)
    {
        return new SampleElements<>(
                Helpers.mapEntry(keys.e0(), values.e0()),
                Helpers.mapEntry(keys.e1(), values.e1()),
                Helpers.mapEntry(keys.e2(), values.e2()),
                Helpers.mapEntry(keys.e3(), values.e3()),
                Helpers.mapEntry(keys.e4(), values.e4()));
    }

    public E e0()
    {
        return e0;
    }

    public E e1()
    {
        return e1;
    }

    public E e2()
    {
        return e2;
    }

    public E e3()
    {
        return e3;
    }

    public E e4()
    {
        return e4;
    }

    public static class Unhashables extends SampleElements<UnhashableObject>
    {
        public Unhashables()
        {
            super(
                    new UnhashableObject(1),
                    new UnhashableObject(2),
                    new UnhashableObject(3),
                    new UnhashableObject(4),
                    new UnhashableObject(5));
        }
    }

    public static class Colliders extends SampleElements<Object>
    {
        public Colliders()
        {
            super(new Collider(1), new Collider(2), new Collider(3), new Collider(4), new Collider(5));
        }
    }

    private static class Collider
    {
        final int value;

        Collider(int value)
        {
            this.value = value;
        }

        @Override
        public boolean equals(Object obj)
        {
            return obj instanceof Collider && ((Collider) obj).value == value;
        }

        @Override
        public int hashCode()
        {
            return 1; // evil!
        }
    }
}
